JR4PWV — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: PM64

Receiver-side FT8 activity involving JR4PWV, decoded by SO8OO in southeastern Poland. 17 FT8 messages attributed to this token as transmitter, on 40m, 20m, across 4 UTC dates in the available aggregate history. Observed between 2026-06-06 and 2026-09-02.

These are automated observations at the SO8OO receiver, not an official contact log. Times are UTC. Attribution follows decoded FT8 message structure: CQ uses the first token and directed-looking messages use the second. Free text that resembles a directed message can be attributed imperfectly. Summary S/N reflects propagation plus SO8OO receiver, antenna and local-noise conditions. Counts are not adjusted for monitoring outages; transmissions that were not decoded are absent. Inferred entity and location data may be inaccurate for portable, remote or special-event operation.

SO8OO decoded 17 FT8 messages attributed to JR4PWV as the transmitting token by decoded message structure across 4 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (65%), followed by 40 m (35%). In this small sample, the estimated median decoder S/N was -5 dB; no usual signal pattern is inferred.

Overview

Messages attributed

UTC dates decoded

Active 15-min windows

-5 dB

Estimated median S/N

Bands

40m · 6 20m · 11

First attributed message: 2026-06-06
Last attributed message: 2026-09-02 20:23 UTC

Observed FT8 message patterns

Attributed sample: 17 messages
Active dates: 4 UTC dates
Estimated median S/N: -5 dB
S/N percentile sample: Too small
Recurring-pattern threshold: Not met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 2, moderate (-15 to -9 dB) 4, strong (≥ -8 dB) 11.

WSJT-X defines S/N reports against a 2,500 Hz reference noise bandwidth. The ranges above are SO8OO receiver-side display categories, not official WSJT-X classes, transmitter-power measurements or estimates of how easy the station is to hear elsewhere. Statistics include only successful decodes on SO8OO's monitored FT8 channels; transmissions that were not decoded are absent. The sample does not meet the threshold for a recurring time or signal-pattern claim (20 attributed messages, three UTC dates and five distinct 15-minute windows).

Frequent counterpart tokens observed at SO8OO

Tokens most often paired with JR4PWV in decoded directed-looking exchanges:

UA3EDQ · European Russia EI4KF · Ireland DJ7M · Fed. Rep. of Germany OH5KNL · Finland PI4DX · Netherlands SP2YY · Poland UA1CEI · European Russia YO7CFD · Romania

Most frequent locator attributed to JR4PWV

The map compares the centres and boundaries of the locator field attributed to this token by decoded message structure, 2° × 1° as a Maidenhead square, and SO8OO's six-character receiver square. The separation is not an exact antenna-to-antenna distance or a radio-path length.

Attributed locator: PM64 · 9 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 8,453 km (approx.)
Last such locator decoded: 2026-09-02 20:23 UTC

A decoded locator can describe portable, remote or special-event operation and is not proof of a permanent station address or transmitter identity.

Observed FT8 exchanges

S/N cells show: decoded at SO8OO / report transmitted by the counterpart. An observed exchange is not a QSL or an official logbook confirmation.

Time UTC	Band	JR4PWV S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-21 16:16	160m	- / -	RA3QTT	-10 / -	4	Partial capture
09-21 16:15	160m	- / -13	UA3EDQ	-8 / -	3	✓ Closing fragment
09-19 20:06	80m	- / -22	SP2YY	+27 / -	4	✓ Closing fragment
09-19 20:05	80m	- / -14	OH5KNL	+9 / -	2	✓ Closing fragment
09-19 19:54	80m	- / -	UX1AA	+3 / -	3	Partial capture
09-19 19:53	80m	- / -21	PI4DX	+6 / -	4	✓ Closing fragment
09-19 19:50	80m	- / -	UX1AA	+8 / -	2	Partial capture
09-19 19:49	80m	- / -3	DJ7M	+20 / -	2	✓ Closing fragment
09-19 19:42	80m	- / -22	UA1CEI	+12 / -	5	✓ Closing fragment
09-19 19:40	80m	- / -	PI4DX	+11 / -	5	Partial capture
09-18 16:00	80m	- / -	UX1AA	-7 / -	6	Partial capture
09-18 16:00	80m	- / -19	SV2JAO	-12 / -	5	Partial capture
09-18 15:59	80m	- / -17	YO7CFD	+6 / -	2	✓ Closing fragment
09-03 16:36	80m	- / -18	UR5ZHJ	-2 / -	2	Partial capture
09-03 16:35	80m	- / -	YO7CFD	+15 / -	3	Partial capture
09-02 20:21	40m	-14 / -	CN8NS	- / -	2	Partial capture
09-02 20:15	40m	-4 / -16	EI4KF	+15 / -13	4	✓ Full exchange observed
09-02 20:10	40m	-16 / -	CN8NS	- / -	2	Partial capture
08-30 16:03	80m	- / -	LY3BRA	+3 / -	5	Partial capture

Recent FT8 messages decoded at SO8OO

Frequency values are decoder audio offsets in hertz, not RF frequencies.

160m

UTC    dB Audio  Message
161545 -14 2146  JR4PWV UA3EDQ KO72
161545 -14 2339  JR4PWV OH2XX -24
161615  -5 2146  JR4PWV UA3EDQ R-13
161615  -9  976  JR4PWV RA3QTT LO01
161645  -5 2146  JR4PWV UA3EDQ 73
161645  -8  976  JR4PWV RA3QTT LO01 (x3)

80m

UTC    dB Audio  Message
195115 +10 2398  JR4PWV UX1AA KO70
195315  +8 2209  JR4PWV PI4DX JO21 (x3)
195445  -2 2398  JR4PWV UX1AA KO70
195445  +6 2209  JR4PWV PI4DX 73
195545  +4 2398  JR4PWV UX1AA KO70 (x2)
200515  +8 2542  JR4PWV OH5KNL -14 (x2)
200615 +28 2544  JR4PWV SP2YY JO93 (x4)
200815  +6 2149  JR4PWV SQ2HEB JO94

40m

UTC    dB Audio  Message
201045 -14 1979  CN8NS JR4PWV PM64 (x3)
201500 +13 2756  JR4PWV EI4KF -16 (x2)
201545  -4 2756  EI4KF JR4PWV R-13
201600 +16 2756  JR4PWV EI4KF RR73
202115 -13 1086  CN8NS JR4PWV PM64 (x2)
202500 -13 1418  JR4PWV CT1EEX IM58

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